Runners high!!!

  Today I'm still a little tired yet amazingly my 56.5 year old body bounced back remarkably well from the 16 miler Monday. I did an easy recovery run yesterday and I realize the importance of these types of runs. Today I had a 4.5 mile tempo run @ 10K pace (7.5mph) on the schedule. In all honesty I was thinking I'd wind up doing some cruise intervals the way I was feeling....yawning...tired...hungry!
   So I chomped a power bar and hit the mill....1 degree incline....1.5 mile warm and cool at reco pace.
   At 1.5 miles I went to 7.5mph and tried to settle in....it seemed a little harder than the last couple of tempo runs....but I concentrated on form,stride and breathing....I broke the run down in my mind into half mile increments...9 of 'em....After about 1.5 miles I thought I'd be good for the distance I had found a rhythm and was cooking along.....by 3 miles I was thinking about quiting and my breathing began to get to the "wheeze". It's hard to explain but this is right on my border line from aerobic to anaerobic....I was working!
  However; since I only had 3 halves to go I held on...after passing 4 miles I was in a new territory....I hadn't suffered like this for a while. I was smooth...in control, and sucking gas!! Right at 4.2 miles into the tempo run I got a rush of endorphins like I hadn't felt in years!!! I was suddenly on another planet! This was amazing because at 4.5 miles, time to cool down...I could have continued! Freaky! Addictive! I'm sitting here thinking "how can I get another one of those rushes!" :)
  Well tomorrow is either a rest or short reco day. I bought a new duffel bag today, Adidas, gettin' ready for a new racing season! I am hoping to get one outdoor run this week....Peace!